Just to update on this issue if anyone else comes across it. Took out the Alarm - it was killing power to all Ignition wires. (Was amazed how easy it was to disable an alarm - scary). I then had power to all units. The separate immobiser is just a card break unit that was disabling the ECU but is working fine so still have some security . I now tried to start the car, but the starter wouldn't and still doesn't turn over (probably iginition switch issue). When bridging the starter, I still had no spark except for an initial one on turning the key to position 2. I have got wasted spark installed as part of the rebuild so after some tooing and froing with MSD - the problem was related to the phase sensor - which we had left disconnected after the rebuild. I though none of the distributor related sensors were required with wasted spark - so that was my mistake. Once this was connected up there was spark. Had to re-time the engine again though, but she started up fine. Just to finish tidying up a few bits and pieces now.